Fatigue and the six hours-on, six-off watch system widely used by mariners were central factors in the October 2016 Nathan E. Stewart tugboat sinking in British Columbia, Canadian safety officials concluded.

Both reports found the Stewart’s second mate dozed off before missing a course change and running aground with the barge DBL 55 on Edge Reef in the entrance to the Seaforth Channel just before 1 a.m.

NTSB officials suggested a pilothouse alerter system — a monitoring system that requires periodic inputs from a crewmember or it sounds an alarm — might have helped avoid the accident. Those alerter systems are being phased in as part of the Coast Guard’s Subchapter M safety requirements for towing vessels.

When he came on that night to pilot the 95’4″x32’x12’, 3,400-hp Nathan E. Stewart and its 287’6″x77’8″x8’ double-hulled barge on a southbound transit to Vancouver, British Columbia, the second mate had slept between 4.5 hours and 6.5 hours on each of the preceding three days — in the morning, but not in his evenings off-watch, the board reported.

“As a result, at the time of the grounding, the second mate had been awake for up to 13 hours,” investigators wrote.

An assistant tankerman was on watch with the second mate, but was off the bridge tending to other duties just before the grounding. After failing to contact the second mate by intercom radio, the tankerman was making his way back up to the bridge when the grounding happened.

Navigational alarms that were turned off or the bridge watch alarm suggested by NTSB officials could have kept the second mate from falling asleep and alerted the other crew members, the TSB investigators wrote.

Battered by swells against the reef, the tug sank about eight hours after grounding, spilling 29,000 gals. of fuel that required a month-long cleanup, and bringing renewed calls for restrictions on petroleum shipments on the Inside Passage.

The TSB report focuses its recommendations on better fatigue management in the industry.

“The use of the 6-on, 6-off shift schedule is a longstanding practice in the marine industry and was not designed according to principles of modern sleep science,” the report declares.

“Although the 6-on, 6-off shift schedule has been called into question by various studies and experts internationally, it continues to be used throughout the marine industry. For example, in this occurrence, the watchkeepers of the Nathan E. Stewart had been working this schedule for over 2 days prior to the grounding. Opportunities to sleep were provided, but the second mate’s inability to nap, combined with the sleep-inducing conditions on the bridge, led to increased fatigue and resulted in the second mate’s falling asleep while on watch.”

There is “a compelling need” for the industry to take on fatigue dangers, and adopt fatigue management plans to keep crews alert, according to the report.

“Implementing effective fatigue education and awareness for watchkeepers is one step that will assist the marine industry in going beyond the regulations to mitigate the risk of fatigue. Implementing comprehensive FMPs within the marine industry will bring it in line with approaches to fatigue management that have already been adopted by the rail and air transportation modes,” the report says.

The board specifically calls for the Canadian Department of Transport to require vessel owners implement comprehensive fatigue management plans specific to their operations.

About the author

Associate Editor Kirk Moore was a reporter for the Asbury Park Press for over 30 years before joining WorkBoat in 2015. He wrote several award-winning stories on marine, environmental, coastal and military issues that helped drive federal and state government policy changes. He has also been a field editor for WorkBoat’s sister publication, National Fisherman, for almost 25 years. Moore was awarded the Online News Association 2011 Knight Award for Public Service for the “Barnegat Bay Under Stress,” 2010 series that led to the New Jersey state government’s restoration plan. He lives in West Creek, N.J.

25 Comments

Not taking time off seriously. 12,’s are even worse I think. Because if ya couldn’t sleep or woke up early. You still have 12 straight hours to stand watch. Wich seems to be too long anyway to be “really”alert for anyway. Boils down to people not taking their job and safety seriously…smh

How does taking your job seriously have anything to do with your ability to sleep? That’s an uneducated opinion stated about studied results. The Navy has been studying 6 hour watches for years and is calling for change, and their research involves information much more factual than “it seems”

This goes back to the time before “Uninspected towing vessels” required any license at all to operate. While inspected vessels with “Masters and Mates” required a three watch system on long voyages the uninspected vessels did not. Then “Operators” of these vessels were licensed but because they were not “Masters and Mates” within the language of the Merchant Marine Officer Competency Act they were exempted from the three watch requirement. Finally when the rules changed and “Operators” became Masters and Mates operating companies successfully argued they should not be required to operate under a three watch system simply because of a name change of their billet. Ludicrous because it was the same argument they had previously used to prevent 3 watch system because they were operators not Masters and Mates. If it’s not safe for a ship to work watch for watch it’s not safe for a towing vessel either. All vessels operating 24 hours a day should be on a three watch system. Period.

33 years of work 6 on and 6 off. Never had a problem with it. In all that time the company I work for has only been 1 accident due to a pilot falling asleep and it happened during the middle of the day. Always wanting to change things because one guy couldn’t sleep in his off time and wasn’t smart enough to pass on to another crew member that he was tired. So period that

I totally agree. I have been working 6 on 6 off for 43 years and you never get used to it. I worked 8 on and 8 off and never was tired. But 12 on and 12 off is ridiculous. Way to long to be watching radar and eye fatigue is very bad

I’ve worked this 6 hr on / 6 hr off watch when I first started in the offshore industry on tugs and workboats for several years before we went to a 12 hr on / 12 hr off watch. The ideal watch would have been 8 hr on / 16 hr off watch or 4 hr on / 8 hr off like some oversea voyages. But alas, due to reduced manning practices some vessel companies put us through, we couldn’t crew up vessels that way.

I agree 100%. The health of the industries towboat and offshore Captains, Mates and General deck crew has fallen to the inth degree. We work a 30/30 schedule in the wheelhouse.. some still maintain 30/15. The deckcrew is 30/15. Everybody works 6 hrs on/6 he’s off. I’ve been told 8 hr watches in the wheelhouse wouldn’t work because one person works 16 hrs and the other only 8 hrs. I totally disagreed. Sleep deprivation is rampant in the industry. What is called “good sleep” on a boat is only a nap anywhere else.

So what plan do they propose. It’s fine to lip service that it’s needed and should be implemented. What does the statement “Specific to their operation” actually do to make companies act??…..fiddlesticks!

Way back when people stood 4 and 8 watches this was not as much of a problem. The regulatory agencies have allowed operators minimum manning rules which exceed common sense. It may not be the most cost efficient way to deal with the situation but what price safety?

Without adding another man to the watch system, there really isn’t any effective way of resolving the issue. Bells, whistles and alarms may help wake you up to avoid a grounding or a collision, however, that is not going to alleviate the underlining issue of fatigue. And let’s be honest – adding another man to the watch is likely not going to happen, because of the increase in labor cost and many boats weren’t built for that many men. Therefore, there is no need to address the issue by creating even more regulations. Captains are becoming clerks with all the paperwork that is already required.

Anyone who believes they can work efficiently whilst doing 6on 6off watches is in denial. It also contravenes MLC 2006 hours of rest requirements. “I can do with only 5.5 hours of sleep” is an out of date macho philosophy of ignorance.

I’ve been working this 6 on 6 off system for 26 years and yes there are times I don’t sleep like I need too but you do that at home or anywhere! If you didn’t sleep well have the crew know so they can maintain a regular schedule to check on you way more often! That’s what I do and it works out fine! All the new rules put out on the health parts with the new health card I will say something will have to change cause if you have sleep apnea they give you more hell about that and the Dr’s can’t get it in there head you can’t sleep a full 8 hours on our jobs!

Of course he fell asleep. six and six watches guarantee you will not get adequate rest according to modern sleep science. Sleep deprivation has been proven to cause permanent brain injury.

Sure, I have worked six and six watches for over forty years without an incident. Guess what? I was lucky. I have experienced micro-sleep, diminished mental acuity, and fatigue due to lack of sleep. Just lucky, that’s the the only thing that separates me from the second mate who got into trouble because he fell asleep. Plain old luck.

If the man on watch was a second mate that means the vessel was crewed with three licensed people for the wheelhouse. The lazy-ass captain should be sanctioned as well. He had enough wheel house personnel to operate a three-watch system yet he put his own comfort ahead of the safety of the vessel. Sounds typical to me of human nature.

Claiming that six and six watches provide adequate rest because I didn’t have a problem is just plain ego-driven denial. Denial of an obvious problem. That problem is the inadequate rest periods aboard two-crew vessels moving tons of cargo with the potential for disaster including the loss of life.

Know why it’s still an issue after fifty years of solid sleep science. Money! That’s it. Plain and simple. I mean, the solution to adequate rest aboard commercial vessels has been around even longer than modern sleep studies. It’s called the three-watch system. Four hours on duty and eight hours off duty. I don’t mean to be Captain Obvious here but the mental masturbation the subject of adequate rest time on vessels generates is comical. Everyone knows the answer to the problem but no one wants to pursue the only viable solution.

Wheelhouse Alerters? oh yeah, thanks for them! Now I have a great alarm clock to wake me up at whatever interval I choose.

I can offer another long-term observation on the marine industry. How many maritime accidents were attributed to other causes while mariner fatigue was never listed as a contributing factor. I personally know of three such accidents over the course of my career, two of which involved fatalities.

What if drunk driving was still being studied endlessly without any change in regulation? How many lives would have been lost over the past fifty years? Fortunately, Drunk Driving regulation was changed and I have no doubt that thousands of people like ourselves owe their lives to an honest and fearless approach to the drunk-driving problem.